Forecast analysis on satellites that need de-orbit technologies: future scenarios for passive de-orbit devices

Propulsion-based de-orbit is a space-proven technology; however, this strategy can strongly limit operational lifetime, as fuel mass is dedicated to the de-orbiting. In addition previous reliability studies have identified the propulsion subsystem as one of the major contributors driving satellite failures. This issue brings the need to develop affordable de-orbit technologies with a limited reliance on the system level performance of the host satellite, ideally largely passive methods. Passive disposal strategies which take advantage of aerodynamic drag as the de-orbit force are particularly attractive because they are independent of spacecraft propulsion capabilities. This paper investigates the future market for passive de-orbit devices in LEO to aid in defining top-level requirements for the design of such devices. This is performed by considering the compliances of projected future satellites with the Inter Agency Space Debris Coordination Committee de-orbit time, to quantify the number of spacecraft that are compliant or non-compliant with the guidelines and, in this way, determine their need for the previously discussed devices. The study is performed by using the SpaceTrak™ database which provides future launch schedules, and spacecraft information; the de-orbit analysis is carried out by means of simulations with STELA. A case study of a passive strategy is given by the de-orbit mechanism technological demonstrator, which is currently under development at Cranfield University and designed to deploy a drag sail at the end of the ESEO satellite mission

Anti-Poverty Strategies for the UK: Poverty and Crime Review

This review of the literature about how and why poverty and crime influence one another, and the benefits to crime reduction of reducing poverty, looks at the implications for practical policies and strategies

Foreign Direct Investment and Pollution Havens

This study empirically investigates the causality relationship between foreign direct investment in the extractive industries and environmental pollution with specific focus on the exploration of natural gas and crude oil. The model of Granger causality tests was used. Two years time-series data for Nigeria covering 2008 and 2009 were used. The study establishes the existence of long-run uni-directional causality relationship flowing from foreign direct investment otherwise, foreign direct investment in minerals extraction to pollution.FDI, Minerals, Pollution, Dependency, Federalism, Gas, Flaring, Development, Africa, Oil, Environment, Governance.

The Dynamics of Gang Criminality and Corruption in Nigeria Universities: A Time Series Analysis

This study contributes to the understanding of the causal relationship between gang culture, criminality and corruption in Nigeria universities where both criminality and corruption are very high complementary variables. Writers on gang culture in Nigeria universities have largely omitted the empirical evaluation of the causal relationship between gang criminality and corruption. This study adopts the time-series models of Granger (1969) to investigate and explain the causality relationship of the variables. Using five years data (2005-2009) from 37 Universities across 36 States of Nigeria and Abuja, the federal capital territory; the results suggest that there is existence of reciprocal relationship between university gang culture, criminality and corruption. The results suggest that there is bi-directional causality relationship flowing between gang criminality and corruption in the universities.Gang, Corruption, University, Nigeria, Education, Time Series, Criminality, Granger, Unit root, Causal link.